Pneumatic gauge



Aug' 18, 1936 R. R. HUNT l PNEUMTIC GAUGE Filed Nov.l, 1929 3 Sheets-Sheet 1 W l W,

Aug. 18, 1936. R. R. HUNT PNEUMATIC .GAUGE 5 Sheets-Sheet 2 Filed Nov. 1, 1929 Aug. 18, 1936. R, Rv HUNT 2,051,258

. PNEUMATIC GAUGE I Filed Nov. 1, 1929l 3 Sheets-sheet 5v 'Jl-@5 a will ...il

Patented Aug. 18,'. 1936 UNITED ISTATES 2,051,258 PNEUMATIC GAUGE Ray R. Hunt, Mishawaka, Ind., assignor to Mishawaka Rubber and Woolen Manufacturing Company, Mishawaka, Ind., a corporation of I ndiana Application November 1, 1929, serial' No. 404,067

'l Claims.

My invention relates to a gauging or measuring method and apparatus wherein the measurement to be tested or, ascertained acts through regulation of fluid in a pressure system to show, in a pronounced manner or on a large scale, slight variations of measurement, this invention being particularly adaptable to pneumatically gauge cr measure and keep a constant check on the thickness of a sheet or layer of material.

In the production of certain materials in sheets or layers it is highly desirable to test or measure and regulate the thickness thereof accurately and maintain a continual check thereon so as to insure uniform and properI gauge or thickness throughout the sheet or layer. This is particularly important in the rubber industry as extra thickness entails a considerable loss, whereas insufficient thickness oftentimes impairs the quality of the goods made from or with the sheet or layer of rubber.

'I'he principal objects ofmy invention are to provide an improved measuring or gauging method and apparatus; to provide a device which is highly sensitive and accurately responsive to slight variations of measurement; to indicate such variations with a high degree of magnification or on a suiiiciently enlarged scale so that they are -rcadily apparent; to accomplish the magnification or enlargement of indication through a medium which acts freely and practically without any frictional or other resistance; to utilize a medium which .aiords a dampening effect to minimize abrupt or violent movements of the indicator;

to dispense with wearing parts and thus insureother layer of material may be accuratelyand conveniently determined; to provide a gauge which may be set for desired thicknesses; to avoid inaccuracies due to changes of temperature, magnetism and other disturbing factors; to permit location of the indicator, if desired, remote from A' thc place where the test or measurementis be- On the drawings:

Fig. 1 is a top view of a gauge constructed in accordance with my inventionfor measuring the thickness of a moving ysheet of material such as rubber;

Fig. 2 is a sectional View on the line 2 2 of Fig. 1 showing one of the gauge units;

Fig. 3 is an enlarged fragmentary view of the gauge unit of Fig. 2 taken from the opposite or outer side; I

Fig. 4 is a front view of the gauge unit;

Fig. 5 is an enlarged vertical sectional View on the line 5--5 of Fig. 4;

Figs. 6 and 7 are detail views illustrating the measuring adjustment which controls the operation of the indicator;

Fig. 8 is a top view of a modified form of the invention for use in gauging the rubber coating on a roll;

Fig. 9 is a sectional View on the line 9-9 of Fig. 8;

Fig. 10 is an enlarged sectional view on the line IIJ-I0 of Fig. 8;

Fig. 11 is an enlarged sectional View on the line II-II of Fig. 8; and

Fig. 12 is a view, somewhat diagrammatic, showing the application of a recording device to my gauge.

Referring to the drawings, and particularly to Figs. l to 'l inclusive, in which Ihave shown an apparatus constructed in accordance with my invention for gauging the thickness of a sheet of rubber as it comes from the rolls of a calendering machine, the reference numeral I indicates the sheet of rubber composition which is' withdrawn from the calendering machine by suitable tape up the take up or winding mechanism, and the sheet I of rubber composition is fed by the tack up or winding mechanism through the gauging appa.

ratus in the direction indicated byl the arrow. Neither the calenderin'g machine nor take up mechanism lis shown as they are old and well known structures. v

A frame of` any suitable construction supports the gauging apparatus, and in the illustrated structure comprises end standards 2- suitably connected by cross members 3 which extend transversely under the sheet I of rubber and beyond the lateral edges thereof.' A shaft 4, which is secured at its ends in brackets 5 on the standards `2, extends under the sheet I of rubber and carries a pair of flat faced idler Wheels o`r rollers 6 over which the sheet I of rubber passes, these wheels or rollers 6 being loosely mounted to rof tate freely on the shaft 4 between collars 1, which outer side thereof and. extending downwardly may be adjusted to locate the rollers 6 as desired.

Preferably a wheel or roller 6 is arranged adjacent and a short distance inwardly fromeach lateral edge of the sheet I. Additional support for the shaft 4 is also afforded by plates I which are mounted respectively at the inner side of each wheel or roller 6 on the cross members 3 of the frame, each plate 3 having a half bearing 3 thereon engaging the under half of the shaft 4 as' shown in Fig. 2.

For guiding the sheet I onto the -rollers 6 and to prevent undesirable sagging thereof be'tween the rollers 6, an idler roll I extends between the standards 2 and is journaled at its ends in bearing plates II on brackets I2, which latter extend upwardly from the respective standard 2. The bearing plates II are secured to the brackets I2 by bolts I3 which engage through slots I4 of the bearing plates and permit adjustment of the latter for properly locating the roll III -close to the wheels or rollers 6 and below the upper extremishaft I5 to permit location of the outer or free end of each supporting arm I6 over a wheel or roller 6. Each arm I6 isformed at its outer end with a housing I3 having a substantially vertical opening I6 therethrough in which a tubular gauge member is mounted to slide axially and held against turning movement by a pair of tubular branches 2| which are secured on and communicate with the interior of the Atube 2li and engage through openings 22 in the wall of the housing I3, said openings 22 being elongated vertically in the form of short slots to permit a limited amount of axial adjustment of the tube 20 in the housing I8. Each housing I3 has a roller 23, mounted thereon at the lower end to move freely to and from the lower end of the tube 20, a pair of plates 24 being secured respectively to the opposite sides of each housing so as to extend therebelow, and the lower projecting ends of each pair of plates 24 being correspondingly slotted as at 25 to receive the trunnions or journals 26 of the roller 23. 'Ihe roller 23 is thus not only free to rotate but also freely movable\ up and down inthe slots 25 to and from the end of the tube 20, being guided in the latter movement by the plates 24- and the slots" 25 thereof, and in its up and down movementl said roller regulates or varies the outlet from the lower end of the tube 20, which preferably has the lower end formed as at 21 to conform to the peripheral face Aof the roller 23.

The sheet'i of rubber or other material to be gauged or measured passes over the supporting and guiding roll I3 and then between the wheels or rollers 6 and the gauge rollers 23 and as the latter rollers ride on and are supported by the moving sheet I, any variation in 'the thickness the eof will cause a corresponding elevation or dep ession of the roller 23 and this in turn will cause a corresponding regulation of the gap between the roller 23 and .the lower end of the tube 20 which is heldin a predetermined fixed position Y vided with a locking pin 46 at the outer end which predetermined position above wheel or roller 6, each housing I3 has an arm 23 secured to the and outwardly therefrom as shown in Fig. 4 and provided at the lower end with an outturned por- 5 tion 29 having a threaded aperture in which an adjusting screw 30 engages and is locked by the lock nut 3|, said adjusting screw preferably havingthe head 32 at the lower end as shown.A A segment gear 33 is loosely mounted on the shaft l0 4 under the lower end ofeach arm 23, it being understood that there is a segment gear 33 adjacent the inner side of each end 'standard 2 of the` supporting frame of the apparatus, each of which is confined on the shaft 4 between a collar 15 34 and the adjoining bracket '5, and these segment gears have corresponding stepped plates 35 at the top thereof with successive stepped cam faces 36, 31, 38, and 33 which may be optionally positioned under the head of the respective ad- 20 justing screw 36, for supporting the respective arm I6 and its gauge mechanism.- Y

These cam faces 36,' 31, 33, and 33 are arranged Y at successive slightly higher elevationsfor readily changing the gauge mechanism to accommodate 25 different thicknesses of sheets I which it may be desired to make, and are adjustable by turning movement of the segment gears 33 which are connected for simultaneous and corresponding movement. To this end a shaft 40 extends from 30 end to end of the supporting frame of the apparatus and is jolunaied at the 'opposite ends in bearings 4I on the standards 2 and this shaft has a pinion 42 xed thereon adjacent each segment gear 33 and meshing with the teeth 43 thereof. 'I 'his shaft 40 projects beyond the bearing 4| at one .end and 'is provided with a hand wheel 44 for turning the shaft, and as the stepped plates 33 arel correspondingly arranged on the segment gears 33, the turning lof the hand wheel 44 and shaft. will bring corresponding cam faces 36, 31, 36, or 39 under the adjusting and supporting screws 30 of both gauging devices so that simultaneous and corresponding adjustment thereof occursl For locking this cam adjusting mechanism in any selected position of adjustment, the shaft 4I has an arm 45 xed thereon between the hand wheel 44 and the adjacent standard 2, and promay be optionally engaged withany of the four openings, (indicated by dottedlines at 41 in Fig.v 3) in a plate 43 (see Fig. 4) which said openings 41 4are spaced and arranged to correspond to the four positions of adjustment of the cam plate 35. For adjusting the gauge tube 26 axially in the housing, the upper end of said tube is closedby a plug 49 which has a threaded opening 53 in the upper end in which the enlarged threaded lower end 5I of the operating stem 52 engages, a 60 shoulder 53 being formed at the upper end of the threaded portion 5I .of the stem to engage a fixed collar 54 at the upper end of the housing Il. 'An

' index plate 55 is secured to the upper end of the housing I8 over the collar 54 andthe stem 52 65 which projects upwardly through the collar 54 and index plate 55 has a knob 56 and dial 5 1 thereon, the former of which is adapted to turn the stem 52 and adjust the elevation of the gauge tube by the threaded connection 56-5I and the 70 latter of which has graduations around the edge co-operating with an index mark 53 on the index plate 55 for convenience in adjusting. The knob 56 and dial 51 are fixed on the stem so as to keep the shoulder 53 of the stem 52 in close engage- 75 ment with the collar 54 and hold the stem $2 -arm of the mercury tube I2 is provided with against axial movement so as to permit accurate adjustments of the gauge tube 2l by turning the knob 56, and the tube 20 may be locked in the various positions of such adjustment by the thumb screw 59 which is threaded through the wall of the housing I8 at a point to engage the plugged upper end of the tube 20. i

In the operation of this gauge air under pressure is maintained in the gauge tube 2li which said pressure varies with-the adjustment of the roller 23 due to variations in thickness of the sheet I, and the variations in thickness of the sheet I are indicated, or recorded if desired, by a device which is responsive to variations in pressure in the gauge tube 20.

The air under pressure is supplied to the tube 20 from any suitable source through `a. tube i0 which connects with the lower branch 2i of the gauge 20, and the pressure in the tube 2l is communicated to the pressure responsive indicating or recording device through the tube II which connects with'the upper branch 2l ofthe gauge tube 20, said tubes 60 and 6I being preferably of a flexible character on account of the movement thereof required in adjusting and moving'. the gauge mechanism, and they may be supported as indicated in Fig. 2 by passing through apertures in the swinging arm IB adjacent the pivoted end thereof.

The air under pressure supplied through the tubes!! for operating this gauge may be obtained in any convenient manner, one method which applicant has found to satisfactorily accomplish the purpose being to provide a supply of air under a pressure greater than that requiredv in the gauge and step it down through one or more ordinary reducing valves. In practice the reducing valve `or valves have been set to supply a maximum pressure of about 15 pounds to the gauge tube and act automatically upon a lowering of the pressure in the gauge tube to supply air thereto.

The instrument for indicating the variations in thickness of the sheet I may be oi' any suitable type which is responsive to variations of pressure in the gauge tube 20, a simple and convenient form being'a U-tube 62 of a -well known type which has the tube 6I connected thereto at one end in the usual `manner so as to cause the mercury therein to rise inthe. arm -63 proportionately to the pressure in the gauge tube 20. Thearm 63 is provided with graduations for determining and comparing the elevations of the mercury column, these vgraduations being preferably spaced to indicate standard units of micrometric measurement usually employed Ain measuring the thickness of the sheet I, and these graduations also preferably being arranged 'in oppositeA series from a zero mark B4 at which the mercury remains when the exact thickness desired is between the rollers 6 and 23. Thus any increase over the required thickness of the sheet will be indicated by a rise of the mercury above the zero mark 64 and any decrease by a lowering of the mercury below the mark 64 and the amount of such increase or decrease will be indicated in units oi.' micrometric measurement isually employed in measuring thickness of sheet material.

A recording instrument may' also be employed to record any variations so that the operator may y keep check on the thickness'without constant attendance. Any suitable recording instrument may be employed, one form being shown s'omewhat diagrammatically in Fig. 1.2 wherein. the

a iloat i5 which' rises and fails with the inercury in the arm B3 and is connected with. a stylus or marker 66 operatingv over a rotating disk 61 upon which the thickness and variations of thickness are recorded. 'I'he disk 61 may be rotated by any usual mechanism or may be' connected for operation b y the movement of the sheet I or by the mechanism which causes such movement so that a certain movement of the dial 61 corresponds to a certain number of feet of length of the sheet I.

In the operation of this gauging device, the machine is first set for the desired thickness by means of test plates of tempered steel or other material of the exact thickness of the sheet 1 that is required. One of these test plates is positioned between each pair oi' rollers 6 and 23 and with the proper cam face 36, 31, 3l, or 3! under the adjusting screw and the air sup- 20 ply system in operation, the adjusting screws 30 are turned until the mercury in the indicator 62 comes to rest and remains at.the zero mark indicated on the drawingsv at 64. Finer adjustnecessary. l

It is to be understood that each of the gauge mechanisms has a separate indicator and air supply or reducing valve so that neither is affect- Y ment may be obtained by turning the knob 56 if 25` ed by the other and each mechanism is set sep- 30.

arately.

When the gauge mechanism is properly set for the desired thickness as indicated in Fig. 5, a gap remains between the roller 23 and the lower end of the tube 20 permitting uniform escape- 35 ment or flow of air from the tube 20 whereas increase in thickness as indicated in Fig. 6 raises the roller 23 and decreases the opening from the lowerend of the tube 20 while decrease in thickness as shown in Fig. 'I lowers the roller 23 and increases the opening from the tube; and it is the uniformity or variation of this gap 'and the resulting uniformity or variation of air leakage or ilow through the gap which affects the pressure in the tube 20 and is communicated to theA indicator 62. Obviously with this leakage the pressure maintained in the tube 2li is less than the roller 23 and the tube 2li increases a lowering of pressure occurs. n

After the gauging mechanism has been properly set, the test plates are removed from between the rollers 6 and 23 and the sheet I of materialstarted through-the` machine. The gauge will then indicate any variation from the desired thickness by rise or fall of the mercury with respect to the zero mark 64 and by adjusting the calender rolls or other mechanism which forms the sheet I and lobserving the eiect on the indicator"62. the exact thickness may be obtained. 65

Any variation in .thickness as the sheet I is .be-

ing produced, will be indicated on the gauge'62 or the recording instrument of Fig. 12 and may be corrected by adjustingA the roller of the machine making the sheet I. l A

In the event that it is desired to turn out sheets I of certain different thicknesses, the steps 36, 31, 38, and 39 are arranged for these particular. thicknesses and the machine may be readily set for these different thicknesses by releasing the thickness 'may be provided for by adjustment of v the `knob 58 and the dial l1 may be graduated to indicate standard micrometric units ofY measurement of thickness so that by turning' the knob 56 and dial the graduations on the dial showing the extent of movement thereof will indicate a definite known change in the thickness of sheet i for which the gauge is set.

Referring to Figs. 8 to '10 inclusive, I have shown my invention arranged to gauge or measure the thickness of a layer or coating of rubber which is to be applied on a sheet of fabric, it being customary in such cases to form the layer or film 68 of rubber composition separately 'on a roll 69 which carries it around and transfers it to and impresses it on the fabric.

For measuring or gauging the thickness of thisl layer or coating 68 of rubber composition, sub`- stantially the same structure as previously dexed distance from theroll, and the rubber layerl scribed is employed except thatthe gauge members require-a somewhat diilerent mounting with special means for holding the gauge tubes at a or lm 68' serves directly, without an interposed roller, tocontrol the opening at the end of the gauge tube.

side portion 12 of the main frame of the machine, which said frame supports the roll 8l, .and the lower ends of the arms 18 of these Abell cranks are connected by a squarebar 14 which is located in front of the roll 88. A bracket 15 is clamped on the bar 14 near each end of the roll 88, said each bracket has an arm 16 projecting toward theroll I8 and .provided atthe outer end with a slit 11 within which a blade `or thin piece 18 vof steel is secured in an upright manner so that the forward edge thereof bears against the periphery of the roll, the arms 18 of the bell cranks Y the gauge tube 28,0! the" previous 831188 structure, being -closed at the outer end by-a plug 84 and provided with lateral tubular branches 85 extending throughslotsll of the housing 82, one

of which said branches 88 is connected by a iiexible tube 81 with a source of air under pressure and the other of which is connected bythe ilex- 'ible tube 88 with a mercury tube indicator 88 like `that of the previous gauge structure or with a recording indicator. one type 'ofwhich is illustrated in., Fig. 12.

'I'he open end of .the gaugetube 8.8 is immediately adjacent the periphery of the roll "so that the layer or coating G8 thereon moves across l' the A open-end' ofthe saute tube with a leakage gap therebetween as lshown in Fig. 10- which varies with'the thickness of the'layeror coating. i

88 andcauses d varlationin leakagey which in turnv causes a' variation of in the gauge vtube 83 which 'is indicatedl by 'the pressure re sponsive device 88.. Y

For adjusting the gauge tubes n tomarrow the m11 aen im simo and am u, the

I aon-,ase

sheet material passed therebetween, and a lires* :latter operating over an index plate 82 on the outer end of the housing 8'2; anda stem 88 on which the knob and dial '9| are secured prejects into the outer end `of the housing 82 and has an enlarged threaded inner end 94 engaging 5 the threaded opening 86 of the plug 84, all in the same manner as the corresponding dial and knob adjusting structure of Figs. l to 7 inclusive.

The blade or thin steel bearings 18 are employed to maintain the lbar 14 and gauge tube Al0 housings 82 at a fixed distance from the roll 89,. inasmuch as the coating 68 of rubber on the roll 69 may extend out to or beyond the bearings 18, and by using the thin blade bearings they cut through the layer of rubber and maintain con- 15 stant contact with the periphery of the roll 68 The operation of this .gauge of Figs. 8 to 11 `inclusive is practically the same as that of Figs. 20

1 to'7 inclusive, the gauge tubes 82 being set at the proper distance from the roll 69 for the desired thickness of the rubber layer or coating 68 which setting positions the mercury in the indicator 89 at the zero point. As the layer or 25 coating 68 is thereafter formed on and carried by the roll 68 across the open ends of the tubes 83 it controls the escape of air therefrom, which will be uniform and maintain 'fa constant pressure in the tubes 8 3 so long as the proper thick- 30 ness of. the layer 88 is maintained. Any variation, however, in the thickness of the layer 68, will cause a variation of leakage fro'xnthe tubes 88 with a consequent' variation of pressure therein and an indication thereof on r the pressure 35 responsive device 88 willl show theinaccuracy of thickness of the layer 88 which is to be corrected. brackets being adjustable along the bar 14, and

'While I have shown and described my invenvtion in a preferred form,I am aware that various changes and modifications may be made without departing from the principles of my invention, the scope of which is to be determined bythe appended claims.

I claim as my invention:

1.5-In a device of the class described the' combination of a roller over which sheet material is passed, a fluid pressure systemhaving an outx lei: at a predetermined distance from the roller,

said roller and outlet being 'adapted to have -the sure responsive means 4connected with the -uid pressure 'system to indicate the thickness of the sheet material cnthe roller. Q

2. In an apparatus of 'the class described the combination of a fluid pressure system having anA 55 outlet, a roller adjacent to said outlet and over which sheetmaterial is passed, said roller and outlet being adaptedA to have the sheet material passed therebetween, means 'for relatively ,adljusting the roller and outlet, and pressure responsive means connected with uid pressure system for gauging the thickness of the sheet material on the roller. 4 -.3. In adevice of theclassdescribed the combination of a fluid pressure system having an 65 outlet, a member free to' move toward and away from said outlet and adapted in such movement4 to regulate the'discharg'e from s aid outlet, means for supporting' moving sheet material ih' position to regulatelthe adjustmentv of said member-ac 70 cording to the thickness 'of said sheet material',

and indicating means which is responsiveto vari-4 ations of pressure in the `iluid pressure system.

'.4. In-va device'of the class described the com-l bination of a drum.' a fluid pressure system hav- 75 and including a surface movable with and upon which the sheet material is supported inv its movement, a fluid pressure system having an outlet at a fixed distance from and discharging toward said surface and said outlet being spaced from the said surface to permit free passage of the sheet material thereby, and pressure responsive means suitably connected with the fluid pressure system to gauge the thickness of the sheet material as it passes the said outlet;

6. In an apparatus of the class described, the combination of a fluid pressure system having an outlet, a rotatable roll on which sheetmaterial is advanced past the outlet, said outlet being positioned to discharge toward the exposed face of thesheet material on the roll, a shoe riding on the face of the roll for holding the outlet at a fixed distance therefrom.' and pressure responsive means connected with the fluid pressure system for gauging the thickness of the sheet material on the roll.

v. In e device ef the class described the eomv bination of a roller over whichisheet material is passed, a. fluid pressure system including a chambered member which has an outlet at a predetermined distance from the roller, said roller and outlet being adapted to have the sheet material lpassed therebetween, and pressure responsive means connected with the fluid pressure system to indicate the thickness oi! the sheet material on the roller, said chambered member being mounted on a swinging support for movement bodily from the operating position and said support having means thereon for graduated adjust- 20 ment of the distance of the outlet from the roller.

Y RAY R. HUNT. 

